> > MessageLabs do not respond with postfix-ish error messages. I mentioned earlier that they reply with a distinct qmail-ish twang when I send an unimplemented command:
220 server-6.tower-36.messagelabs.com ESMTP
foobar
502 unimplemented (#5.5.1)
No other MTA that I know of implements enhanced status codes by
putting them as (#X.Y.Z) within free text.
Wietse
